Water Quality and Treatment Review Introduction

MEMORANDUM

Hillsboro Water Supply Options—TM#6 - Water Quality and Treatment Review

TO: Alan Peck, P.E. Carmen Nale, P.E.

FROM: Paul Berg, P.E. Lee Odell, P.E. Joe Broberg, P.E., BCEE, PMP Brad Phelps, P.E.

DATE: December 2, 2011 PROJECT NUMBER: 407893.01.02

Introduction This memorandum identifies the treatment processes needed for each of the four additional water supply sources being considered by the City of Hillsboro. The recommended treatment processes would produce treated water similar to the quality of water currently supplied by the Joint Water Commission (JWC) system. The recommended processes are based on a review of existing water quality data. The four additional water supply sources being considered are: 1. Tualatin Basin Water Supply Project (TBWSP) Option: This option would draw raw, untreated water from an expanded Hagg Lake through the JWC System. 2. Willamette-Newberg Option (East and West Sub-Options) and the Willamette- Wilsonville Option: These three options would draw raw, untreated water from the Willamette River from the Newberg pool, which extends from the City of Newberg, River Mile 51, downstream to Willamette Falls at Oregon City, River Mile 26.5; The water would be treated to provide treated water similar in quality to that provided by the existing JWC system. 3. Portland Supply Option: This option would purchase disinfected water from the Portland Water Bureau (PWB). The PWB draws from two raw water sources with distinctly different water qualities, Bull Run and the Columbia River Well Field. The Columbia River Well Field Supply is used when turbidity levels in the Bull Run Supply are high. Water from the City of Portland would be treated to provide treated water similar in quality to that provided by the existing JWC system 4. Northern Groundwater Supply Option (NGSO): This option would pump raw, untreated groundwater from the area between the City of Scappoose and Multnomah Channel. The raw water would be treated to provide treated water similar in quality to the existing JWC system.

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A fifth source, the Tualatin River near Durham, was identified but does not have sufficient capacity to meet Hillsboro’s demands and cannot obtain a water right. Therefore, it was removed from consideration in the preliminary screening prior to water quality review. Described below are the pertinent regulatory requirements and the water quality data sources. These are followed by an evaluation of the water quality data, review of water quality risks, determination of treatment requirements to effectively mitigate that risk, and conclusions about the water quality issues associated with each of the candidate water supply sources, including a recommendation for additional water quality sampling as part of advancing the design work on the next stage of alternative selection.

Regulatory Background Public water systems in Oregon are regulated by the U.S. Environmental Protection Agency (EPA), primarily through the 1996 Amendments to the Safe Drinking Water Act, and by the Oregon Department of Human Services—Drinking Water Program. To maintain primacy for the enforcement of the Safe Drinking Water Act (SDWA), Oregon must adopt water quality regulations that are at least as stringent as EPA’s standards. Oregon has adopted water quality standards equal to EPA’s standards and has not adopted more stringent water quality standards. EPA has established enforceable Maximum Contaminant Levels (MCLs) for approximately 100 contaminants and treatment technique requirements for other contaminants. MCLs are set to protect the public against consumption of drinking water contaminants that present a risk to human health. In addition, EPA has established secondary regulations that set non-mandatory water quality standards for 15 contaminants. EPA does not enforce these Secondary Maximum Contaminant Levels (SMCLs). They are established only as guidelines to assist public water systems in managing their drinking water for aesthetic considerations, such as taste, color, and odor. These contaminants are not considered to present a risk to human health at the SMCL. EPA is in a continuous process of reviewing occurrence and health effects data for additional contaminants that are not currently regulated to determine if new MCLs are warranted. The SDWA includes a process that EPA follows to identify and list unregulated contaminants which may require a national drinking water regulation in the future. EPA periodically publishes this list of contaminants (called the Contaminant Candidate List or CCL) and decides whether to regulate additional contaminants. The list of unregulated contaminants is also used to prioritize research and data collection efforts to help EPA determine whether a specific contaminant should be regulated. The first CCL (CCL 1) of 60 contaminants was published in March 1998, the second CCL 2 of 51 contaminants was published in February 2005, and the final CCL 3 of 104 chemicals or chemical groups and 12 microbiological contaminants was published October 2009. The list includes chemicals used in commerce, pesticides, biological toxins, disinfection byproducts, and waterborne pathogens. The contaminants on the list are not regulated by existing national primary drinking water regulations, are known or anticipated to occur in public water systems, and

2 HILLSBORO WATER SUPPLY OPTIONS—TM#6 - WATER QUALITY AND TREATMENT REVIEW may require regulation. EPA evaluated approximately 7,500 chemicals and microbes and selected 116 candidates for the Final CCL 3. EPA is considering developing regulations for contaminant groups as well as developing new regulations for individual contaminants. The strategy of regulating groups of contaminants was also highlighted in the October 2010 Regulatory Update prepared by J. Alan Roberson, the American Water Works Association Director of Security and Regulatory Affairs. Roberson summarized EPA’s new drinking water strategy as consisting of the following four components: 1. Address groups of contaminants (emerging contaminants). 2. Promote use of new technologies for both monitoring and treatment. 3. Leverage use of existing statutes such as the Toxic Substances Control Act for protecting source waters. 4. Promote easy access to utility monitoring data. Since regulatory requirements for endocrine disrupting chemicals (EDCs) and pharmaceuticals and personal care products (PPCPs) are still being developed, there is some risk in developing a new source for Hillsboro before regulatory requirements are known. Among the contaminant groups being considered by EPA are the following EDCs and PPCPs: estrogenic compounds, androgenic (steroid hormone) compounds, pharmaceuticals, and antibiotics. Depending on source water quality, treatment performance and changing regulatory requirements, there is a risk that Hillsboro’s new treatment plant may need to be upgraded to meet possible future but unknown regulations at a higher incremental cost as compared to installation at the time of original plant construction. However, good treatment plant design to proactively mitigate the major contaminants being considered by the EPA should conservatively situate Hillsboro in a minimal risk position. Therefore, this memo has selected effective mitigating treatment processes for each source option for all of the contaminants that identified in the specific source option. Another emerging contaminant for which regulations are being developed is algal toxins. Algae blooms have affected reservoirs upstream of surface water supplies for Salem, Medford, and other Oregon cities. One group of algal toxins, microcystins, has been detected in algal blooms in several lakes and reservoirs in Oregon. EPA has placed algal toxins on the Contaminant Candidate List for consideration for future regulation.

Water Quality Data Sources Water quality data were obtained from the following reports collected by GSI (GSI) Water Solutions, Inc. from various sources and provided for this study:

 Water Quality Monitoring Activities dated August 2007.

 Willamette River Water Treatment Pilot Study Executive Summary dated August 2004.

 Willamette River Raw Water Monitoring Program 1994-1996.

 Willamette River Raw Water Monitoring Program 1998-1999.

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 Willamette River Raw Water Monitoring Program 1999-2000.

 Willamette River Raw Water Monitoring Program 2001-2002.

 Willamette River Raw Water Monitoring Program 2003 and 2004.

 Finished water quality comparison for JWC, City of Portland, and Wilsonville sources in 2003 and 2004.

 Finished water quality comparison for JWC, City of Portland, and Wilsonville sources in 2005 and 2006.

 Report prepared by Alexin Analytical Laboratories for a sample of JWC water collected in August 2009. Data for the occurrence of personal care products and other anthropogenic compounds associated with wastewater discharges were obtained from the 2002 USGS report Water- Quality Data for Pharmaceuticals, Hormones, and Other Organic Wastewater Contaminants in U.S. Streams, 1999-2000. Additional data describing the quality of the Portland Supply were obtained from the City of Portland.

Evaluation of Source (Raw) Water Quality Data This section evaluated the quality of the supply option source water to identify appropriate treatment processes or state the water quality of a source option is a fatal flaw for that option. The water quality data evaluated for this memorandum are summarized in Table 1, which is included at the end of this memorandum. Water quality data were summarized for the following six categories: 1. Customer acceptance parameters (e.g. water quality parameters of aesthetic concern to customers after treatment.) 2. Inorganic chemical parameters of the source water. 3. Microbiological quality of the source water. 4. Disinfection byproducts expected after treatment of the source water. 5. Organic chemical parameters of the source water. 6. Radionuclides in the source water. No fatal flaws were identified which would eliminate any of the options based on raw water quality. Based on available source water quality data, all options will require further treatment using available treatment technologies to produce finished water that meets drinking water standards. Table 1 summarizes regulatory requirements for treated water, quality of treated water currently delivered by JWC, quality of the sources available to Hillsboro, and the treatment processes needed to produce treated water similar to that currently delivered by JWC. Raw water quality data is provided for two of the sources, the Willamette-Newberg Pool and NGSO, since the treatment processes would need to treat raw water to produce treated water similar to that currently delivered by JEC. Water quality data for the PWB source is after disinfection, since Hillsboro would purchase disinfected water from the PWB and treat it further to produce water similar in quality to that currently delivered by the JWC system.

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The data provided by GSI did not include occurrence data for EDCs and PPCPs for the source options. These are currently not regulated as drinking water contaminants. Therefore, water systems do not regularly monitor for these contaminants. State and federal agencies have performed limited monitoring for these contaminants but only in recent years as advances have been made in analytical techniques to allow measurements at nanogram per liter levels. A majority of EDC’s and PPCP’s are effectively addressed by ozonation and granular activated carbon filtration coupled with conventional water treatment processes. Very limited data is available for the TBWSP Option since the dam raise has not been constructed and therefore available water quality data is limited to the existing non- expanded dam environment. Additionally, no data was available for the other three sources for two water quality concerns, blue-green algae and the toxins they may produce, and taste and odor compounds. Both of these elements however can be treated using ozonation and granular activated carbon filtration coupled with conventional water treatment processes.

Water Quality Considerations – TBWSP After Treatment by JWC The JWC system provides treated water meeting customer requirements and regulatory requirements for drinking water. The City of Hillsboro has determined that water from other sources would need to be similar in quality to that provided by the JWC system. The following discussion reviews the water quality provided by JWC in each of six categories. Since water from the TBWSP would be stored in Hagg Lake and treated and delivered by JWC, water quality from this option is assumed to be similar to that provided by the existing JWC system. Customer acceptance criteria Treated water delivered by JWC has low concentrations of dissolved solids and hardness and moderately low concentrations organic carbon. Low concentrations of dissolved solids and hardness are desirable, especially for industrial uses. Low concentrations of organic carbon are desirable for industrial uses and also limit the formation of disinfection byproducts. Neither iron nor manganese were detected in the treated water. If present, iron and manganese may cause undesirable staining of fixtures and laundry. No data was available for silica concentrations in the finished water. If present, silica affects the use of water for some industrial operations. Inorganic Parameters Of the inorganic chemicals for which data was available, only nitrate was detected in JWC finished water. High concentrations of nitrate would be a concern for some infants. The concentration of nitrate was less than 10 percent of the regulatory limit. Microbiological quality Treated water delivered by the JWC system is of high microbiological quality, consistently meeting regulatory requirements. Disinfection byproducts Treated water delivered by the JWC system meets regulatory requirements for disinfection byproducts, with maximum concentrations of less than 50 percent of the regulatory limit.

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Organic Chemical Parameters JWC analyzes its water for all regulated organic chemicals and 41 additional unregulated organics. None of the organic chemicals for which laboratory data was available were detected. No data were available for EDCs and PPCPs. Radionuclides No radionuclides have been detected in treated water delivered by the JWC system.

Water Quality Considerations - Willamette Newberg Option (West and East Sub Options) and the Willamette Wilsonville Option The Willamette Newberg (West and East Sub Options) and the Willamette Wilsonville Option Raw will draw raw water from the Newberg Pool of the Willamette River. Water from the Newberg Pool is currently being treated at the Willamette River Water Treatment Plant (WRWTP) at Wilsonville. For contaminants regulated following treatment, it is assumed that data available from treated water produced by the WRWTP predicts the performance of a new water treatment plant that would supply Hillsboro provided that new treatment plant uses similar treatment processes as currently being used in the WRWTP. Customer acceptance criteria Raw water from the Newberg Pool has low concentrations of dissolved solids and hardness and moderately low concentrations organic carbon similar to water supplied by JWC. Iron was not detected in the treated water. Manganese was detected in the raw water at a concentration that requires treatment. Silica was detected in the raw water. Since no silica data was available for the JWC source, it is not known if raw water from the Willamette has a higher or lower silica concentration than the JWC source. Silica affects the use of water for some industrial operations. Raw water from the Willamette has an earthy odor associated with algae and treatment would be needed to produce water similar in quality to that provided by JWC. Total organic carbon (TOC) values for the Willamette River generally ranged from 1.0 to 2.0 mg/L. One very high value was reported (18 mg/L) but it is unclear if this was an actual value or in error. There is no MCL for TOC but TOC levels drive treatment techniques for surface water supplies because TOC may contribute to the formation of disinfection by-products. Regulations require enhanced coagulation processes for TOC levels in excess of 2.0 mg/L. In addition to contributing to disinfection by-products, TOC also may adversely affect some industrial uses such as semiconductor manufacturing. Inorganic Parameters Of the inorganic chemicals for which data was available, a very low concentration of arsenic was detected in one sample of raw water, a very low concentration of nickel was detected in one sample of raw water, and nitrate was detected at levels similar to that found in water supplied by JWC. No arsenic has been detected in treated water at the WRWTP. Nickel is not currently regulated as a drinking water constituent and was present at a concentration lower than that proposed for regulation. The concentration of nitrate was less than 10 percent of the regulatory limit. Microbiological quality Giardia has been detected in a small number of raw water samples from the Newberg Pool. No giardia has been detected in treated water produced by the WRWTP. Bacteria are

6 HILLSBORO WATER SUPPLY OPTIONS—TM#6 - WATER QUALITY AND TREATMENT REVIEW assumed to be present in the raw water, but are removed by water treatment processes. Bacteria have not been detected in treated water produced by the WRWTP. Disinfection byproducts Disinfection byproducts are produced by chlorination of raw water containing naturally occurring organic carbon. Treated water produced at the WRWTP meets regulatory requirements for disinfection byproducts, with maximum concentrations of less than 50 percent of the regulatory limit. Organic Chemical Parameters Raw water from the Newberg Pool has been analyzed for the presence of 191 different organic chemicals. A very low concentration of metalachlor was detected in one raw water sample. Very low concentrations of atrazine, simizine, and DEHP have been detected sporadically in a handful of samples and a consistent trend is not apparent from sampling for organic chemicals in raw water from the Newberg Pool. No data for EDCs and PPCPs are available for the Newberg Pool. Existing data do not provide sufficient information to assess the presence of EDCs and PPCPs in the Willamette Newberg Option (East and West Sub Options) and the Willamette Wilsonville Option or the risk presented by EDCs and PPCPs if they are present. Additional data would help verify if EDCs and PPCPs are present and that ozonation and adsorption with granular activated carbon will remove the EDCs and PPCPs that are found. Radionuclides No radionuclides have been detected in raw water from the Newberg Pool.

Water Quality Considerations - Portland Supply Option The Portland Supply Option will draw source water from the PWB water system. This PWB system draws from both from unfiltered surface and ground water sources. Surface water from impoundments in the Bull Run watershed is supplied when turbidities are low. When turbidities are higher than the regulatory limit of 5 NTU in the Bull Run watershed, the Portland water system supplies ground water from its Columbia Wellfield. Treatment for both sources is limited to disinfection using chloramines and pH adjustment to limit corrosion of customer service pipes. Customer acceptance criteria Water from the PWB system varies greatly in dissolved solids and hardness concentrations. Water from the Bull Run watershed has low concentrations of dissolved solids and hardness. Manganese is detected at higher concentrations than in water delivered by JWC in water from the Bull Run watershed and the Columbia Wellfield. Iron is detected in water from the Columbia Wellfield, but not the Bull Run watershed. Water from the Columbia Wellfield has concentrations of dissolved solids up to four times higher than in water delivered by JWC and hardness from twice to seven times higher than in water delivered by JWC. Silica has been detected in water from the Bull Run watershed. Since no data is available for silica in water from the JWC system, it is not possible to compare the silica concentration in the two supplies.

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Inorganic Parameters Of the inorganic chemicals for which data was available, very low concentrations of cyanide (less than 25 percent of the regulatory limit) have been detected in water from the Bull Run watershed. The concentration of nitrate was highest in water from the Columbia Wellfield, but was less than 6 percent of the regulatory limit. Microbiological quality The PWB system provides effective treatment for bacteria, but not giardia nor cryptosporidum. Giardia has been detected in one sample from the Bull Run Watershed, but is generally not detected. Some of the Portland reservoirs are not covered, creating the possibility of contamination. If Portland’s system continues to remain unfiltered, water supplied to Hillsboro from the Portland system would require filtration to be compatible with Hillsboro’s other water supplies. Without treatment, the higher turbidity levels from the Portland system may be problematic for some customers, particularly electronic manufacturers. It is likely that a direct filtration process would provide acceptable treatment. Disinfection byproducts Disinfection byproducts are produced by chlorination of raw water containing naturally occurring organic carbon. Treated water produced at the Wilsonville Water Treatment Plant meets regulatory requirements for disinfection byproducts, with maximum concentrations of less than 40 percent of the regulatory limit. Organic Chemical Parameters Regulated organic chemicals have been not been detected in the Portland Water system. Low concentrations of several PPCPs, including acetamenophin, sulfamethoxazole, estradiol, and ethinyl estradiol, have been detected in the Portland sources. Since no data is available for EDCs and PPCPs in other sources, it is not possible to assess the occurrence of these chemicals relative to other sources. Radionuclides A very low concentration (less than 7 percent of the screening level) of one regulated radionuclide, beta particles, has been detected in water from the Bull Run watershed. One unregulated radionuclide, radon, has been detected in water from the Bull Run watershed.

Water Quality Considerations – Northern Groundwater Supply Option The NGSO will draw water from wells in the Columbia Alluvium between the City of Scappoose and Multnomah Channel. Limited water quality data was available from existing wells in the area. The groundwater is assumed to be similar in quality to that produced from the City of Portland Columbia Wellfield. If the Northern Groundwater source alternative is selected for implementation, additional water quality data will need to be collected from test wells. The data would be used to assess the presence of regulated water quality parameters, agricultural chemical contaminants, EDCs, PPCPs, and other constituents of interest. In addition the possible impact of contaminated sites near the confluence of the Willamette River and Multnomah Channel should be evaluated in more detail. It would be desirable to have sampling data available from at least one test well. It would be desirable to collect samples quarterly for a year (four well pumping tests). The concentrations of arsenic, iron,

8 HILLSBORO WATER SUPPLY OPTIONS—TM#6 - WATER QUALITY AND TREATMENT REVIEW and manganese are of particular interest. Groundwater from the Northern Groundwater Supply Option may be classified as groundwater under the influence of surface water, which will affect choice of treatment processes. Additional groundwater modeling would be needed to assess the impact of water from Multnomah Channel, the Columbia River, and local ponds that might be drawn in by pumping. Customer acceptance criteria Raw groundwater from the NGSO is expected to have concentrations of dissolved solids three to four times higher than those in water currently delivered by JWC. Raw ground water is expected to have hardness concentrations six to ten times higher than those in water currently delivered by JWC. Iron and manganese are expected to be present at high enough concentrations to exceed customer acceptance. Only one iron value was reported for the proposed wellfield between the City of Scappoose and Multnomah Channel, and it was slightly below the iron SMCL. The mean and average values for dissolved iron in samples from wells on Sauvie Island exceeded the SMCL of 0.3 mg/L. All mean and average values for dissolved manganese in the three Northern Groundwater zones exceeded the SMCL of 0.05 mg/L. No data was available for silica concentrations in the groundwater. If present, silica affects the use of water for some industrial operations. Organic carbon is expected to be present at concentrations acceptable to customers. Inorganic Parameters Several arsenic exceedances were associated with shallow sand layers that are expected to be above the zones that will be pumped. A number of samples from Sauvie Island south of the proposed wellfield exceeded the arsenic MCL of 0.010 mg/L. The concentration of nitrate is assumed to be less than 10 percent of the regulatory limit. The concentration of other regulated inorganic chemicals is assumed to be well below regulatory limits. Microbiological quality Raw groundwater from the NGSO is assumed to be groundwater under the influence of surface water. Disinfection byproducts Disinfection byproducts produced during treatment are assumed to be below regulatory limits. Organic Chemical Parameters No organic chemical data were reported for the Northern Groundwater sources. A groundwater withdrawal may affect recharge patterns and influence the potential for contamination of the Northern Groundwater source from the Columbia River. One result may be shortened travel times from Multnomah Channel and the Columbia River to the Northern Groundwater aquifer, which could increase concentrations of organic chemicals, EDCs, and PPCPs concentrations in the groundwater supply if these contaminants are present in the river. Radionuclides No data is available for radionuclides in water produced by NGSO.

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Treatment Requirements All four of the water sources available to the City of Hillsboro can be treated to provide finished water meeting requirements of the Safe Drinking Water Act. Treatment requirements for each source have been evaluated based on a review of existing water quality data. The treatment required for each source is presented below:

 TBWSP Option: Due to the likely changes in the source water quality when the Scoggins Dam is raised, water drawn from Hagg Lake and treated at an expanded Joint Water Commission Water Treatment Plant using existing treatment processes with the addition of ozone would continue to meet the requirements of the City of Hillsboro. Raw water for the TBWSP Option should be treated using ozone, coagulation and flocculation, sedimentation, filtration with dual media, and disinfection with chlorine.

 Willamette Newberg (West and East Sub Option) and the Wilsonville Option: The Willamette River presents a low risk option if the water is appropriately treated. Water from the Willamette River can be successfully treated using the treatment processes currently in place at the Willamette River Water Treatment Plant at Wilsonville. The treatment experience at the existing WRWTP at Wilsonville provides good guidance for determining treatment requirements for this source. These processes include pretreatment by coagulation and flocculation, ballasted sedimentation, ozonation (for primary disinfection, organics removal, and taste and odor control), deep bed media filtration using granular activated carbon (GAC) over sand media, and post-disinfection using chlorine. As additional water quality data become available, the treatment processes should be re-evaluated for continued applicability. The impact of mixing treated water drawn from the Willamette River with existing supplies should also be evaluated. The combination of ozonation plus GAC adsorption is likely to be effective in removing a broad range of organic chemicals, including EDC and PCP compounds. Ozonation is also effective for removing algal toxins and taste- and odor-causing compounds. The addition of EDC and PPCP compounds to existing sampling programs would provide additional data that could be used to further evaluate treatment processes.

 Portland Supply Option: The Portland Supply Option presents a low risk option if the water is treated. Treatment would be needed to remove chloramines, filter to provide an additional barrier removing microbiological contaminants and reduce elevated turbidity levels, and rechlorinate to provide water similar to that currently provided by JWC. Split stream reverse osmosis might be required to reduce dissolved solids and hardness as the system switches between the Bull Run Supply and the Columbia River Wellfield supply. The City of Hillsboro uses free chlorine to disinfect and maintain a residual. The City of Portland uses a combination of chlorine and ammonia (chloramines) to disinfect its sources. The chloramines would need to be removed from City of Portland water to be compatible with the Hillsboro system. As additional water quality data become available, they should be evaluated. The impact of mixing water from the Portland Supply Option system with existing supplies should be evaluated.

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 Northern Groundwater Supply Option: Raw water from the Northern Groundwater Supply Option should be treated using chlorine oxidation to precipitate iron and manganese, coagulation and flocculation, filtration with dual media, split stream reverse osmosis to remove dissolved solids and hardness, and disinfection with chlorine. The impact of mixing treated water drawn from the Northern Groundwater Supply Option with existing supplies should also be evaluated.

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TABLE 1 Summary of Source Water Quality and Treatment Requirements by Source Regulatory Requirement Willamette Newberg Portland Supply Option or Guidance (EPA unless (East and West Sub otherwise listed) Options) and the Northern TBWSP Option P=Primary regulation Willamette Wilsonville Groundwater Supply (After treatment Criteria S=Secondary regulation) option Bull Run Columbia Wellfield Option by JWC) Description Source water assessment Surface water from; Treated surface water Treated groundwater Groundwater assumed Surface water upstream urban from protected watershed; from Blue Lake, under the influence of from forested development, agricultural treated by chloramination Troutdale Sand, and surface water; watershed with activity, and forests Sand and Gravel aquifers Columbia River limited rural treated by chloramination alluvium development and small number of roads Recommended Not a regulated parameter Coagulation and For Hillsboro portion For Hillsboro portion (36 Iron and manganese Coagulation, treatment processes flocculation, ballasted sand (36 MGD) to meet MGD) to meet customer removal, coagulation flocculation, to match treated sedimentation, ozonation, customer requirements: requirements: Oxidation and flocculation, ozonation, water currently sedimentation, deep bed Oxidation to remove to remove chloramines, granular media sedimentation, delivered by JWC granular media filtration chloramines, coagulation, coagulation, flocculation, filtration, split stream granular media with GAC over sand, flocculation, ozonation, ozonation, sedimentation, reverse osmosis, filtration, disinfection with chlorine sedimentation, granular granular media filtration, disinfection using disinfection with media filtration, disinfec- disinfection with chlorine chlorine chlorine tion with chlorine For others: No additional For others: No additional treatment treatment Customer Acceptance Parameters (Water quality parameters of concern to Customers) Total dissolved solids <500 mg/L (S) 53 to 76.8 mg/L 18 to 35 mg/L 17 to 270 mg/L 175-220 mg/L 60 to 74 mg/L pH (after pH 6.5 to 8.5 (S) 7.67 to 8.11 7.8 to 8.2 7.1 to 8.5 6.3 to 8.3 7.33 to 7.6 adjustment)

Hardness <250 mg/L (Oregon S) 22.4 to 28.2 mg/L 5.9 to 8.1 mg/L as CaCO3 52 to 220 mg/L as 25 to 200 mg/L as 26 to 32 mg/L as CaCO3 CaCO3 CaCO3 Silica None 13 to 17 mg/L (USGS) 3.8 to 4.9 mg/L No data No data No data Iron <0.3 mg/L (S) ND ND 0.012 to 0.11 mg/L 0.05 to 0.65 mg/L >0.3 mg/l Manganese <0.05 mg/L (S) 0.004 mg/L (treated water) 0.002 to 0.012 mg/L 0.0010 to 0.46 mg/L 0.001 to 0.40 mg/L >0.05 mg/l Total organic carbon 2 mg/L trigger in raw 1 to 2 mg/l in raw water, 0.95 to 1.5 mg/L in treated ND to 1.5 mg/L in No data 0.83 to 0.88 mg/L water for enhanced with one report of 18 mg/l water treated water coagulation <0.8 mg/L in treated water

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TABLE 1 Summary of Source Water Quality and Treatment Requirements by Source Regulatory Requirement Willamette Newberg Portland Supply Option or Guidance (EPA unless (East and West Sub otherwise listed) Options) and the Northern TBWSP Option P=Primary regulation Willamette Wilsonville Groundwater Supply (After treatment Criteria S=Secondary regulation) option Bull Run Columbia Wellfield Option by JWC) Others: Color, odor Varies Earthy odor associated Acceptable Acceptable No data No color, no odor with algae (raw water) data Inorganic Chemical Parameters Arsenic <0.010 mg/L One sample at ND ND 0.001 to 0.023 mg/L in ND in production 0.0006 mg/L in raw water, shallow sand alluvium zone, Detected at ND in treated water at Sauvie Island 0.01 mg/l or more in shallow sands Lead and copper Lead<0.15 mg/L; copper Traces of lead in treated Treated water is mildly corrosive to lead plumbing No data Not corrosive <1.3 mg/L water materials Nitrate <10 mg/L as N 0.3 to 0.8 mg/L 0.01-0.04 (Raw water) ND to 0.64 mg/L No data 0.6 to 1.0 mg/L Fluoride EPA < 4mg/L ND ND No data No data ND Other regulated: Varies ND or well below Cyanide at 0.046 mg/L; Below standard or ND 0.005 mg/L in shallow ND or well below Antimony, barium, regulatory limit Below standard of sands on Sauvie regulatory limit beryllium, cadmium, 0.2 mg/L Island, Below chromium, cyanide, regulatory limit of mercury, selenium, 0.002 mg/L sulfate, thallium Other secondary or Varies ND except one sample Below standard or ND No data No data ND nonregulated: with low concentration of Aluminum, silver, nickel zinc, nickel Microbiological Quality Turbidity Varies, <0.3 NTU for 0.037 to 0.039 NTU 0.2 to 1.6 NTU 0.7 mg/L No data <0.04 NTU treated water, <5 for untreated water Bacteria Goal of zero; required ND (treated water) Uncovered reservoirs present risk of contamination No data; Assumed Raw water is treatment technique from waterfowl and storm events, Chloramination under influence of assumed to be only treatment. surface water under influence of surface water, ND (treated water)

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THMs (after <0.08 mg/L (P) 0.00562 to 0.00591 mg/L 0.021 mg/L No data 0.028 to treatment) 0.0388 mg/L Haloacetic acids <0.06 mg/L ND to 0.00195 mg/L 0.042 mg/L No data 0.030 mg/L (after treatment) Organic Chemical Parameters Regulated organic Varies ND except DBPs and ND No data ND except DBPs chemicals (50 sporadic atrazine, chemicals) simizine, and DEHP at very low concentration Personal care No regulations or No data for Newberg Pool; Sporadic, very low Sporadic, very low No data No data products and guidance concentrations of concentrations of pharmaceuticals caffeine, acetaminophen, acetaminophen, ibuprofen, caffeine, sulfamethoxazole, estradiol, ethinyl estradiol, possible sampling or lab contamination Unregulated organics No regulations or ND except for one No data No data No data ND for 41 or organics proposed guidance instance of metachlor at analyzed for regulation (41 <0.000001 mg/L; Analyzed chemicals) for additional 160

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Regulated Varies 1 sample in 2002 - Gross Beta particles at 3.4 picocuries/L, below screening No data ND radionuclides: Alpha alpha, radium, and level of 50 picocuries/L particles, Beta uranium detected well particles and photon below regulatory emitters, radium 226 standards and 228, uranium (P)

Radon (unregulated) No regulation 1 sample in 2002 - ND 145 picocuries/L No data ND

ND = Not detected